ios-core 0.1.6

//! Pairing credential persistence.
//!
//! Saves/loads the host identity generated during SRP pairing.
//! Stored as JSON at a platform-specific path.

use std::path::PathBuf;

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PersistedCredentials {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub remote_identifier: Option<String>,
    pub host_identifier: String,
    /// Ed25519 public key (hex-encoded)
    pub host_public_key_hex: String,
    /// Ed25519 private key seed (hex-encoded) used for future verifyManualPairing.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub host_private_key_hex: Option<String>,
    /// Base64-encoded remote unlock host key returned by createRemoteUnlockKey.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub remote_unlock_host_key: Option<String>,
    /// IPv6 address of the paired device
    pub device_address: String,
    /// RSD port at time of pairing
    pub rsd_port: u16,
}

impl PersistedCredentials {
    /// Default directory for storing pair credentials.
    pub fn default_dir() -> PathBuf {
        if cfg!(target_os = "macos") {
            dirs_next::home_dir()
                .unwrap_or_else(|| PathBuf::from("/tmp"))
                .join(".ios-rs")
        } else if cfg!(windows) {
            std::env::var("APPDATA")
                .map(PathBuf::from)
                .unwrap_or_else(|_| PathBuf::from("C:\\ProgramData"))
                .join("ios-rs")
        } else {
            dirs_next::home_dir()
                .unwrap_or_else(|| PathBuf::from("/tmp"))
                .join(".ios-rs")
        }
    }

    /// Compatibility directory used by pymobiledevice3 remote pairing records.
    pub fn pymobiledevice3_dir() -> PathBuf {
        dirs_next::home_dir()
            .unwrap_or_else(|| PathBuf::from("/tmp"))
            .join(".pymobiledevice3")
    }

    /// Path to the credential file for a specific device.
    pub fn path_for(dir: &std::path::Path, device_addr: &str) -> PathBuf {
        let safe_addr = device_addr.replace([':', '%'], "_");
        dir.join(format!("{safe_addr}.json"))
    }

    /// Save to disk.
    pub fn save(&self, dir: &std::path::Path) -> std::io::Result<()> {
        std::fs::create_dir_all(dir)?;
        let path = Self::path_for(dir, &self.device_address);
        let json = serde_json::to_string_pretty(self).map_err(std::io::Error::other)?;
        std::fs::write(path, json)
    }

    /// Load from disk by device address.
    pub fn load(dir: &std::path::Path, device_addr: &str) -> Option<Self> {
        let path = Self::path_for(dir, device_addr);
        let json = std::fs::read_to_string(path).ok()?;
        serde_json::from_str(&json).ok()
    }

    /// List all saved credentials in a directory.
    pub fn list(dir: &std::path::Path) -> Vec<Self> {
        let Ok(entries) = std::fs::read_dir(dir) else {
            return vec![];
        };
        entries
            .filter_map(|e| e.ok())
            .filter(|e| e.path().extension().map(|x| x == "json").unwrap_or(false))
            .filter_map(|e| std::fs::read_to_string(e.path()).ok())
            .filter_map(|s| serde_json::from_str(&s).ok())
            .collect()
    }
}

#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
pub struct RemotePairingRecord {
    pub public_key: Vec<u8>,
    pub private_key: Vec<u8>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub remote_unlock_host_key: Option<String>,
}

impl RemotePairingRecord {
    pub fn path_for_identifier(dir: &std::path::Path, remote_identifier: &str) -> PathBuf {
        dir.join(format!("remote_{remote_identifier}.plist"))
    }

    pub fn save_for_identifier(
        &self,
        dir: &std::path::Path,
        remote_identifier: &str,
    ) -> std::io::Result<()> {
        std::fs::create_dir_all(dir)?;
        plist::to_file_xml(Self::path_for_identifier(dir, remote_identifier), self)
            .map_err(std::io::Error::other)
    }

    pub fn load_for_identifier(dir: &std::path::Path, remote_identifier: &str) -> Option<Self> {
        plist::from_file(Self::path_for_identifier(dir, remote_identifier)).ok()
    }

    pub fn list(dir: &std::path::Path) -> Vec<(String, Self)> {
        let Ok(entries) = std::fs::read_dir(dir) else {
            return vec![];
        };

        entries
            .filter_map(|entry| entry.ok())
            .filter_map(|entry| {
                let path = entry.path();
                let file_name = path.file_name()?.to_str()?;
                let remote_identifier = file_name
                    .strip_prefix("remote_")?
                    .strip_suffix(".plist")?
                    .to_string();
                let record = plist::from_file(&path).ok()?;
                Some((remote_identifier, record))
            })
            .collect()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_roundtrip() {
        let dir = std::env::temp_dir().join("ios_rs_test_creds");
        let cred = PersistedCredentials {
            remote_identifier: Some("test-remote".into()),
            host_identifier: "test-id".into(),
            host_public_key_hex: "deadbeef".into(),
            host_private_key_hex: Some("cafebabe".into()),
            remote_unlock_host_key: Some("host-key".into()),
            device_address: "fd00::1".into(),
            rsd_port: 58783,
        };
        cred.save(&dir).unwrap();
        let loaded = PersistedCredentials::load(&dir, "fd00::1").unwrap();
        assert_eq!(loaded.remote_identifier.as_deref(), Some("test-remote"));
        assert_eq!(loaded.host_identifier, "test-id");
        assert_eq!(loaded.rsd_port, 58783);
        assert_eq!(loaded.host_private_key_hex.as_deref(), Some("cafebabe"));
        assert_eq!(loaded.remote_unlock_host_key.as_deref(), Some("host-key"));
        // cleanup
        let _ = std::fs::remove_dir_all(&dir);
    }

    #[test]
    fn test_backward_compatible_load_without_private_key() {
        let dir = std::env::temp_dir().join("ios_rs_test_creds_legacy");
        std::fs::create_dir_all(&dir).unwrap();
        let path = PersistedCredentials::path_for(&dir, "fd00::2");
        std::fs::write(
            &path,
            r#"{
  "host_identifier": "legacy-id",
  "host_public_key_hex": "deadbeef",
  "device_address": "fd00::2",
  "rsd_port": 58783
}"#,
        )
        .unwrap();

        let loaded = PersistedCredentials::load(&dir, "fd00::2").unwrap();
        assert_eq!(loaded.host_identifier, "legacy-id");
        assert!(loaded.host_private_key_hex.is_none());
        assert!(loaded.remote_identifier.is_none());
        assert!(loaded.remote_unlock_host_key.is_none());

        let _ = std::fs::remove_dir_all(&dir);
    }

    #[test]
    fn test_remote_pairing_record_roundtrip() {
        let dir = std::env::temp_dir().join("ios_rs_test_remote_pair_record");
        let record = RemotePairingRecord {
            public_key: vec![0x01, 0x02, 0x03],
            private_key: vec![0x04, 0x05, 0x06],
            remote_unlock_host_key: Some("PcV5xhyuJBL7Qq9HOGeGVwtU4sJLe1jtl/vRy1tRKcI=".into()),
        };

        record
            .save_for_identifier(&dir, "00008150-000D6D6A1122401C")
            .unwrap();

        let loaded =
            RemotePairingRecord::load_for_identifier(&dir, "00008150-000D6D6A1122401C").unwrap();
        assert_eq!(loaded, record);

        let listed = RemotePairingRecord::list(&dir);
        assert_eq!(listed.len(), 1);
        assert_eq!(listed[0].0, "00008150-000D6D6A1122401C");
        assert_eq!(listed[0].1, record);

        let _ = std::fs::remove_dir_all(&dir);
    }
}